Sheet-lifting device working with suckers



March 19, 1 929, v G. @1555 memos- SHEET LIFI'ING DEVICE WORKING WITHSUCKERS Filed Sept. 22, 1927 -2 sheets sheet 1 h 19, 1929. v a. SPIESS 95 SHEET LIF'TING DEVICE WORKING WITH SUCKBRS I Filed Sept. 22, 192'? 2SheetS SMQt Z Patented Mar. 19,1929.

flum'rao STATES GEoRGsr Ess; or LEIrzIG-rLAGwIrz, GERMANY.

snnn'r-Lmzrme DEvIoE WORKING WITH sucxnns.

Application filed- September 22, 1927, Serial No. 221,378 and in GermanySeptember 25, 1926.

It has become known to blow, in sheet lifting devices which work withsuckers, air between the sucked-on portion'of thetop-sheet and the pileof sheets in order to facilitate the separation of the uppermost sheetwhich has been sucked onat one edge and lifted from the pile. WVhen thesheet is lifted by the suckers on the front-edge and pulled off, theblowing air acts in a direct-ion'opposite to that in which the sheet isbeing pulled off and the suckers must, as they have toovernected withthe gripper aws, under the bent portion of the top-sheet between thissheet and the pile. Only a very feeble sucking effect is consequentlyrequired as the same is necessar only for bending avery small portion oftl i off of the sheet from the pile is ensured as the sheeti's securelygripped by the mechanical gripper jaws. The blowing nozz'lesco-operating with the gripper jaws are, according to the invention,either directly fixed to the movable gripper jaw which grips thetop-sheet from below, so that they participate in the movement ofthe'same, or stationarily mounted preferably on the support of thegripper-1 aw.

It is advisable to direct two different blowin air-jets between theportion of sheet lifted y the suckers and the pile, the one along thelower surface of the lifted sheetportion to facilitate pulling off ofthe top sheet from the pile, and the other directly against theuppersurface of the pile for holding down the next following sheets. Theblowing nozzles are preferably adjustably arranged under the movablegripper jaw, either stationarily'or movable with the gripper jaw, or theone nozzle stationary and the other movable. .The blowing nozzles mayhave a common supply-pipe and a common regulation or they may have eachits own supply-pipe. The strength of each blowing alret may be regulatedindividu all].

geveral'embodimen tsof the invention are ment of the separators relativeto e top-sheet so that a reliable pulling illustrated, by way ofexample, in the. accompanying drawings, in whichi- Fig.1 shows inelevation the total arrangement of the device Fig. 1 is aplanviewshowing the arrangethe sheet pile. I Fig. 2 shows on larger scale thecarrier for the sheet-lifting device, the blowers being mounted on themovable gripper jaw.

Fig. 3 is a Vew similar to Fig. 2, the blow ers being mounted on thecarrierof the gripper Jaw.

Fig. 4 illustrates a form of construction of a gripper jaw with twoblowing nozzles connected with the samei q Fig. 5 shows on larger scaleand in perspective View the connection of the gripper jaw with theblowers.

Referring to Fig. 1, the sheet-pile is designed by 1; Qis a pile-plate,3 the machineframe, 4 the driving shaftfrom which, by spur-wheels 5 and6, a shaft"? is rotated on which, at either side of the pile 1, armsSare mounted so that";v they can be adjusted in transverse direction.These arms 8 carry the. sheet lifting device and-pull the sheet off thepile by an oscillating movement. To-the arms 8 suction nozzles 9 arehingedlycon levers and control-cams so that, after the.

sheet-corners have been lifted by the suckers -9, they grip undenthelifted sheet-corners and clamp the same in co operation with thesuction-nozzles so that no further suckingwork is required. It is notnecessary to specially describe in which manner the suckers and gripperjaws are operated as they .do not form part of the invention.

nected, designed to suck on and liftlithe.

The grippers 12, which clamp the lifted sheet-corners against thesuction-nozzles 9, have blowing-nozzles 13 from,which a channel leads toa tubular-connection M on which a hose 15 is fixed. The other end ofhose 151 is attached to a tubular socket of an airchannel provided inthe carrier '15- of the op-- crating levers for the gripper jaws. Theother tubular-connection of the air-channel is connected by a hose 17with the controlapparatus for the blowing air.

In the form of construction shown in Fig.

3 a blowing air-nozzle 18 is rigidly fixed to the carrier for theoperating levers of the gripper jaws and connected to the hose 17' byits tubular-connection 19. The nozzle 18 is arranged at such aheight,with regard to the arm 8, that the jet of blowing air is directed underthe sheet-corners sucked on and lifted by the suckers 9. The blowingair. is controlled in, such 'a manner that it position by means of aclamping screw 21.

The arms of said holder embrace the gripperhub from bothsides. On thebottom of the holder 22 a blower 2 5 is clamped by means ,ofa-clampingebow 23 and clamping screws- 24, the hose, 1'? for the blowingair being connected to said blower. The, blower- 25 comprises twoblowing nozzles 26, 27, the

nozzle 26 being directed so that the out-flowing air blows along thelower surface of the lifted portion of the sheet, the nozzle 26beingdownwardly directed towards the surface of the pile so that theblowing air presses the sheets onto the pile. Both noz- 'zles 26, 27 arearranged directly under the gripper jaw 12 and execute the samemovements as the. gripper jaw. The blowing nozzles may be, adjusted onthe rocking-shaft 20 with regard to the gripper'jaw12 after loosening ofthe clamping-screw ,21 v. and turning of the holder 22, so that thedirection of the jets of blowing air can always be adjusted inaccordance with the manner of working of the sucker and of the gripperjaw.

it is not necessary that the blowing-nozzles 26,27 participate in' theoscillatingmovement-of the, gripper jaw. They may be both stationary, oronly the nozzle 26 may be stationary the nozzle 27 being connected withthe gripper jaw. Each blowing-nozzle may evidently have its ownsupply-conduit, and the strength of each blowing jet may be regulatedindividually. v

011 the pile.

.onto the 1' claim: 1. A sheet lifting device working with suckers,comprising in combinationwith the suckers designed to lift thefront-corners of the top-sheet from .the pileofgripper jaws for clampingthe front-edge of the lifted top-sheet against the suckers and forpulling said sheet off the pile, and blowing nozzles coroperating -withsaid gripper jaws for blowing, air into the gap between the liftedfront-portion of the top-sheet-and the pile.

2. A sheet liftingdevice as specified in claim 1, comprising incombination with each gripping jaw, two blowing nozzles, one

of said nozzles being directed so that the jet of blowing air blowsalong the lower surface 'of the lifted sheet-portion, the otherblowingnozzle being downwardly directed towards the pile so that theair-jet holds the sheets] 3. A sheet lifting device as specified inclaim 1, comprising in combination with each gripper jaw, twoblowing-nozzles underneath said gripper jaw one directed so that theair-jet 'blows along the lower surface of the lifted portion of thesheet, the other being downwardly directed to blow the air onto thepile.-

4. A sheet lifting device as specified in claim 1, comprising incombination with a gripper aw, a rock1ng-shaft,'a U-shaped holder: forthe gripper jaw 'adjustably' mounted on said rocking-shaft, and twoblowing-nozzles in said holder under said gripper jaw one blower nozzlebeing directed so that the air-jet blows along the lower surface of thelifted portion of the sheet and 'the'other nozzle being directed to blowthe air downwardly onto the pile.

5. A sheet lifting device as specified in claim 1, comprising incombination with a rock shaft, a gripper jaw'adjustably mounted on saidshaft, and two blowing nozzles carried by the shaft and disposedbeneathand adjustable with the gripper jaw, one

nozzle being directed so that the 'air jet blows along the lowersurfaceof the lifted portion of the sheet and the other nozzle beingdirected toblow the air downwardly ile.

v In testi fnony whereof I affix my signature.

GEORG SPlESS.

